Polymers and copolymers of, and surgical devices made from, lactide and/or glycolide and/or related compounds are well-known. See, e.g., U.S. Pat. Nos. 2,668,162, 2,683,136, 2,703,316, 2,758,987, 3,225,766, 3,268,486, 3,268,487, 3,297,033, 3,422,181, 3,442,871, 3,463,158, 3,468,853, 3,531,561, 3,565,869, 3,597,449, 3,620,218, 3,626,948, 3,636,956, 3,736,646, 3,739,773, 3,772,420, 3,733,919, 3,781,349, 3,784,585, 3,792,010, 3,797,499, 3,839,297, 3,846,382, 3,867,190, 3,987,937, 3,878,284, 3,896,802, 3,902,497, 3,937,223, 3,982,543, 4,033,938, 4,045,418, 4,057,537, 4,060,089, 4,137,921, 4,157,437, 4,243,775, 4,246,904, 4,273,920, 4,275,813, 4,279,249, 4,300,565, and 4,744,365, U.K. Pat. or Appln. Nos. 779,291, 1,332,505, 1,414,600 and 2,102,827, D. K. Gilding et al., "Biodegradable polymers for use in surgery-polyglycolic/poly (lactic acid) homo-and copolymers: 1, "Polymer, Volume 20, pages 1459-1464 (1979), and D. F. Williams (ed.), Biocompatibility of Clinical Implant Materials, Volume II, chapter 9: "Biodegradable Polymers" (1981).
Surgical devices prepared from copolymers containing lactide or glycolide and trimethylene carbonate have been described, for example, in U.S. Pat. No. 4,429,080 which describes glycolide-trimethylene carbonate random copolymers and triblock copolymers having glycolide end blocks and glycolide-trimethylene carbonate random copolymer middle blocks. The block copolymers described in the '080 patent contain no lactide.
As another example, U.S. Pat. No. 5,066,772 describes random copolymers of lactide and trimethylene carbonate and triblock copolymers having lactide end blocks and lactide-trimethylene carbonate random copolymer center blocks. The block copolymers of the '772 patent do not include a block which is predominantly glycolide. In addition, see U.S. Pat. Nos. 4,243,775; 4,300,565; 4,705,820; 4,891,263; 4,916,193; and 4,920,203.